The present invention relates to a tubular air cleaner arranged in an intake air passage of an internal combustion engine.
A prior art tubular air cleaner for an internal combustion engine includes a tubular housing and a tubular filter element. The housing includes a circumferential wall including an inlet, a top wall including an outlet, and a bottom wall opposed to the top wall. The filter element is accommodated in the housing.
The tubular filter element includes a pleated tubular filter portion, which is formed by pleating a filter medium sheet, and two sealing portions, which are arranged on opposite ends of the filter portion in an axial direction to seal the space between the top wall and the bottom wall of the housing.
Japanese Laid-Open Patent Publication No. 2001-123897 discloses a filter element that includes a filter portion and an inner tube, which is located at an inner side of the filter portion. The inner tube includes an adsorbent, which adsorbs evaporated fuel, and has a number of air holes.